Most of techniques in 4th Edition boil down to equivalent of "for this specific purpose, you act like your relevant trait was 1 higher than it is".
That's a vast oversimplification.
It is a simplification, I agree. Still, I think it's accurate one - most of techniques give you a bonus that is as efficient as having appropiate Trait higher by 1 than your current stat. This usually means that you either roll flat out +1k1, or that you get anywhere from 3 to 7 in flat numbers - because that's what, realistically/optimistically, you would be able to keep if you had one more dice to keep. After all, +5 or a Free Raise is pretty much "automatically rolling and keeping dice with 5 on it". In general, techniques that give you numerical benefit can be contested by having your trait "+1", as you noted. So this is a simplification that kind of agrees with your point about compensating for techniques with stats .
(Kakita technique is a special snowflake here, because it's vastly overstacked; the +1k1 on Focus Roll would be a perfect example, but the scaling bonus of +School Rank breaks "the rule"; still, for most of the game, it's more of a tie-breaker than anything else)
If you want to get little more complex, there are also techniques that give you a special ability of some kind, but they are both rarer, and harder to balance.